Turf grass is used for a variety of purposes, such as maintaining appearances, preventing fires and providing recreation space within golf courses, parks, household gardens, river bed, and orchard grounds and the like.
One of the problems associated with maintaining appearances while ensuring healthy growth of the grass is the control of weeds. Further, weeds that multiply within grass can inhibit growth of the grass, and the seeds of those weeds can stick to clothing and provide breeding grounds for insect pests.
Accordingly, weeds that multiply within grass have conventionally been controlled using a herbicide. However, in control methods using conventional herbicides, a variety of problems tend to arise, including a narrow weed killing spectrum for the herbicide, leading to an unsatisfactory control effect, restrictions in terms of the treatment method, a narrow timeframe for optimum treatment, and environmental safety issues.
Furthermore, in recent years, weeds that have developed resistance due to repeated application of the same herbicides have also become problematic.
In relation to the present invention, the fact that 1,5-diphenyl-1H-1,2,4-triazole-3-carboxamide derivatives exhibit a herbicide activity has already been disclosed in Patent Document 1 and the like. Flupoxam, which is one of the compounds disclosed in this document (ISO name: flupoxam; CAS name: 1-[4-chloro-3-[(2,2,3,3,3-pentafluoropropoxy)methyl]phenyl]-5-phenyl-1H-1,2,4-triazole-3-carboxamide, Reg. No. 119126-15-7), has been registered in Europe as a herbicide for wheat and barley.
Furthermore, flupoxam has also been supplied to The Japan Association for Advancement of Phyto-Regulators for testing as a soil-based herbicide for grass in 2002. It is known that flupoxam has no detrimental effects on turf grasses such as Zoysia japonica and Zoysia tenuifolia, while exhibiting a powerful control action on broadleaf annual weeds such as chickweed and gramineous weeds such as crabgrass that can grow in grass (see Non-Patent Document 1).
However, until now it was not known that flupoxam also exhibits excellent weed control activity for broadleaf perennial weeds that grow in grass, and weeds that have resistance to conventional herbicides.
[Patent Document 1]    Japanese Unexamined Patent Application, First Publication No. S63-313779    [Non-Patent Document 1] Spring-summer 2003 edition of test results for grass-related herbicides and growth regulators—(published December 2003 by The Japan Association for Advancement of Phyto-Regulators)